In a move seen by the Pentagon as aggressive, Iraq has moved surface-to-air missile batteries into the no-fly zones in the north and south of the country, increasing the threat to U.S. and other allied warplanes on patrol.

This is not the first time Iraq has moved missiles into the no-fly zones.

But in disclosing the latest threat, General Richard Myers, Chairman of the Joint Chiefs of Staff of the U.S. armed forces, calls it the most extensive move in the past two years. General Myers said, "Some of these movements of surface-to-air missile systems into regions where we enforce the no-fly zone under the U.N. resolutions are greater than they have been in a couple of years."

General Myers gave no additional details other than to say the deployments have taken place in recent days.

But he said it points out the dangers posed to American military personnel by a country whose intentions he characterizes as worrisome. He said, "We tend to forget that we have Americans being shot at on a fairly regular basis in other parts of the world besides Afghanistan in a country that we're worried about their intentions."

Just a week ago, coalition aircraft patrolling the southern no-fly zone came under hostile fire and responding by attacking Iraqi anti-aircraft systems with precision-guided weapons.

And only last Friday, Iraqi air-defense radars actively targeted coalition planes in the northern no-fly zone, prompting strikes on what the Pentagon termed elements of Iraq's integrated air defense system.

In both case, all coalition aircraft departed the areas safely.

U.S. and British warplanes have been enforcing the no-fly zones since the end of the Gulf War.